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Yes,
You can create a custom domain for your blog. There are instructions on blogger for each of the major registrars, and you can do this without transferring your content.
All of the blogs listed in my signature are blogspot blogs for which I have created a custom domain.
It's fairly easy to do, but slightly different for each registrar.
Then when you want to sell (after getting your money tucked safely into your account), you can sell and transfer the domain to the buyer as you normally would. And then you can send an invitation to the buyer to become a team member of the blog. Once he or she accepts, you make that person an administrator with directions for him or her to delete you as a team member.
Just make sure that your adsense has been turned off before doing this.
The buyer will probably have to redo the instructions for creating a custom domain.
Good luck!
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